U.S. patent application number 14/854496 was filed with the patent office on 2016-03-24 for elevator shaft inner dimension measuring device, elevator shaft inner dimension measurement controller, and elevator shaft inner dimension measurement method.
The applicant listed for this patent is Kabushiki Kaisha Toshiba. Invention is credited to Ryuzo OKADA, Akihito SEKI, Masaki YAMAZAKI.
Application Number | 20160084649 14/854496 |
Document ID | / |
Family ID | 55525485 |
Filed Date | 2016-03-24 |
United States Patent
Application |
20160084649 |
Kind Code |
A1 |
YAMAZAKI; Masaki ; et
al. |
March 24, 2016 |
ELEVATOR SHAFT INNER DIMENSION MEASURING DEVICE, ELEVATOR SHAFT
INNER DIMENSION MEASUREMENT CONTROLLER, AND ELEVATOR SHAFT INNER
DIMENSION MEASUREMENT METHOD
Abstract
According to one embodiment, an elevator shaft inner dimension
measuring device includes a distance measuring instrument, an
imaging device and a controller. The distance measuring instrument
includes a first laser rangefinder mounted to a moving object
moving through an interior of an elevator shaft, and irradiating
laser light on an inner wall of the elevator shaft. The imaging
device includes a first camera mounted to the moving object, and
imaging the interior of the elevator shaft. The controller includes
a calculator, a position calculating device, and a memory device.
The calculator performs an operation on distance data obtained from
the distance measuring instrument, and image data obtained from the
imaging device. The position calculating device estimates a motion
of the moving object and calculates a position of the moving object
in the interior of the elevator shaft. The memory device stores the
distance data and the image data.
Inventors: |
YAMAZAKI; Masaki; (Tokyo,
JP) ; SEKI; Akihito; (Yokohama, JP) ; OKADA;
Ryuzo; (Kawasaki, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Kabushiki Kaisha Toshiba |
Tokyo |
|
JP |
|
|
Family ID: |
55525485 |
Appl. No.: |
14/854496 |
Filed: |
September 15, 2015 |
Current U.S.
Class: |
348/139 |
Current CPC
Class: |
G01S 17/88 20130101;
G01S 17/08 20130101 |
International
Class: |
G01C 3/00 20060101
G01C003/00; H04N 7/18 20060101 H04N007/18 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 19, 2014 |
JP |
2014-191085 |
Claims
1. An elevator shaft inner dimension measuring device, comprising:
a distance measuring instrument including a first laser rangefinder
mounted to a moving object moving through an interior of an
elevator shaft, the first laser rangefinder irradiating laser light
on an inner wall of the elevator shaft; an imaging device including
a first camera mounted to the moving object, the first camera
imaging the interior of the elevator shaft; and a controller
including a calculator, a position calculating device, and a memory
device, the calculator performing an operation on distance data and
image data, the distance data being obtained from the distance
measuring instrument, the image data being obtained from the
imaging device, the position calculating device estimating a motion
of the moving object based on the image data and calculating a
position of the moving object in the interior of the elevator shaft
based on the distance data, the memory device storing the distance
data and the image data.
2. The device according to claim 1, wherein the first laser
rangefinder irradiates the laser light toward the inside of an
imaging range of the first camera.
3. The device according to claim 1, wherein the moving object is an
elevator car moving through the elevator shaft in two
directions.
4. The device according to claim 1, wherein the moving object is a
counterweight moving through the elevator shaft in two
directions.
5. The device according to claim 1, wherein the distance measuring
instrument sets an irradiation angle of the laser light based on a
distance between a projection region and a center position of an
image and based on a distance between the projection region and the
inner wall, the image being imaged by the imaging device, the
projection region being an irradiation region of the laser light
projected onto the image.
6. The device according to claim 1, wherein the position
calculating device calculates the position of the moving object in
the interior of the elevator shaft by acquiring a true scale of the
motion based on the distance data.
7. The device according to claim 1, wherein the first camera is an
omni-directional camera capable of imaging the inner wall in 360
degrees around an axis of a movement direction of the moving
object.
8. The device according to claim 1, wherein the imaging device
further includes a second camera mounted to the moving object, the
second camera imaging the interior of the elevator shaft.
9. The device according to claim 8, wherein an imaging range of the
second camera and at least a portion of an imaging range of the
first camera overlap.
10. The device according to claim 8, wherein a positional
relationship between the first camera and the second camera is
calibrated, and the position calculating device calculates the
position of the moving object in the interior of the elevator shaft
by acquiring a true scale of the motion based on the calibrated
positional relationship.
11. The device according to claim 1, further comprising a rotating
device holding the first laser rangefinder and modifying an
irradiation angle of the laser light.
12. The device according to claim 11, wherein the rotating device
modifies a position of the first laser rangefinder or an angle of
the first laser rangefinder while a position of the imaging device
is fixed.
13. The device according to claim 1, wherein the distance measuring
instrument further includes a second laser rangefinder mounted to
the moving object, the second laser rangefinder irradiating laser
light on the inner wall of the elevator shaft.
14. The device according to claim 1, wherein the first camera is a
digital camera capable of receiving visible light or infrared
light.
15. An elevator shaft inner dimension measurement controller,
comprising: a calculator performing an operation on distance data
and image data, the distance data being obtained from a distance
measuring instrument including a laser rangefinder mounted to a
moving object moving through an interior of an elevator shaft, the
laser rangefinder irradiating laser light on an inner wall of the
elevator shaft, the image data being obtained from an imaging
device including a first camera mounted to the moving object, the
first camera imaging the interior of the elevator shaft; a position
calculating device estimating a motion of the moving object based
on the image data and calculating a position of the moving object
in the interior of the elevator shaft based on the distance data;
and a memory device storing the distance data and the image
data.
16. The controller according to claim 15, wherein the position
calculating device calculates the position of the moving object in
the interior of the elevator shaft by acquiring a true scale of the
motion based on the distance data.
17. The controller according to claim 15, wherein the imaging
device further includes a second camera mounted to the moving
object, the second camera imaging the interior of the elevator
shaft, a positional relationship between the first camera and the
second camera is calibrated, and the position calculating device
calculates the position of the moving object in the interior of the
elevator shaft by acquiring a true scale of the motion based on the
calibrated positional relationship.
18. An elevator shaft inner dimension measurement method,
comprising: performing an operation on distance data and image
data, the distance data being obtained from a distance measuring
instrument including a laser rangefinder mounted to a moving object
moving through an interior of an elevator shaft, the laser
rangefinder irradiating laser light on an inner wall of the
elevator shaft, the image data being obtained from an imaging
device including a first camera mounted to the moving object, the
first camera imaging the interior of the elevator shaft; estimating
a motion of the moving object based on the image data and
calculating a position of the moving object in the interior of the
elevator shaft based on the distance data; and storing the distance
data and the image data.
19. The method according to claim 18, including calculating the
position of the moving object in the interior of the elevator shaft
by acquiring a true scale of the motion based on the distance
data.
20. The method according to claim 18, wherein the imaging device
further includes a second camera mounted to the moving object, the
second camera imaging the interior of the elevator shaft, a
positional relationship between the first camera and the second
camera is calibrated, and the position of the moving object in the
interior of the elevator shaft is calculated by acquiring a true
scale of the motion based on the calibrated positional
relationship.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is based upon and claims the benefit of
priority from Japanese Patent Application No. 2014-191085, filed on
Sep. 19, 2014; the entire contents of which are incorporated herein
by reference.
FIELD
[0002] Embodiments described herein relate generally to an elevator
shaft inner dimension measuring device, an elevator shaft inner
dimension measurement controller, and an elevator shaft inner
dimension measurement method.
BACKGROUND
[0003] In the preparation stages when performing the replacement or
repair of an elevator, work is performed to ascertain conditions
inside the elevator shaft and measure the dimensions of the parts
inside the elevator shaft necessary to make drawings. The work is
performed by an operator entering the elevator shaft and measuring
the dimensions using a tape measure, etc.
[0004] However, because the operator performs the work by measuring
the dimensions while riding on the elevator car, for example, time
and labor are necessary in the case where the measurement distance
is relatively long, etc.
[0005] It is desirable to measure the dimensions inside the
elevator shaft relatively easily or in a relatively short period of
time.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] FIG. 1 is a block diagram showing an elevator shaft inner
dimension measuring device according to an embodiment;
[0007] FIG. 2 is a flowchart describing the elevator shaft inner
dimension measurement method according to the embodiment;
[0008] FIG. 3 is a schematic plan view showing the elevator shaft
inner dimension measuring device according to the embodiment;
[0009] FIG. 4 is a schematic plan view showing a modification of
the mounting method of the elevator shaft inner dimension measuring
device;
[0010] FIG. 5 is a schematic plan view showing another modification
of the mounting method of the elevator shaft inner dimension
measuring device;
[0011] FIG. 6 is a schematic plan view showing another modification
of the mounting method of the elevator shaft inner dimension
measuring device;
[0012] FIG. 7A to FIG. 7C are schematic plan views showing examples
of the projection region of the irradiation region of the laser
light projected onto the image that is imaged;
[0013] FIG. 8A and FIG. 8B are schematic views showing examples of
motion estimation charts of the first camera;
[0014] FIG. 9A and FIG. 9B are schematic views showing another
example of motion estimation charts of the first camera;
[0015] FIG. 10 is a schematic view showing an example of a scale
estimation chart of the first laser rangefinder;
[0016] FIG. 11 is a schematic plan view showing an elevator shaft
inner dimension measuring device according to another
embodiment;
[0017] FIG. 12 is a block diagram showing an elevator shaft inner
dimension measuring device according to a modification of the
embodiment;
[0018] FIG. 13A and FIG. 13B are schematic plan views showing
rotation states of the laser rangefinder;
[0019] FIG. 14A and FIG. 14B are schematic plan views showing other
rotation states of the laser rangefinder;
[0020] FIG. 15 is a block diagram showing an elevator shaft inner
dimension measuring device according to one other embodiment;
[0021] FIG. 16 is a flowchart describing an elevator shaft inner
dimension measurement method according to the one other
embodiment;
[0022] FIG. 17 is a schematic plan view showing the elevator shaft
inner dimension measuring device according to the one other
embodiment;
[0023] FIG. 18 is a schematic plan view showing an elevator shaft
inner dimension measuring device according to another
embodiment;
[0024] FIG. 19 is a block diagram showing an elevator shaft inner
dimension measuring device according to a modification of the
embodiment;
[0025] FIG. 20A and FIG. 20B are schematic plan views showing
rotation states of the laser rangefinder; and
[0026] FIG. 21A and FIG. 21B are schematic plan views showing other
rotation states of the laser rangefinder.
DETAILED DESCRIPTION
[0027] According to one embodiment, an elevator shaft inner
dimension measuring device includes a distance measuring
instrument, an imaging device and a controller. The distance
measuring instrument includes a first laser rangefinder. The first
laser rangefinder is mounted to a moving object moving through an
interior of an elevator shaft, and irradiates laser light on an
inner wall of the elevator shaft. The imaging device includes a
first camera. The first camera is mounted to the moving object, and
images the interior of the elevator shaft. The controller includes
a calculator, a position calculating device, and a memory device.
The calculator performs an operation on distance data and image
data. The distance data is obtained from the distance measuring
instrument, and the image data is obtained from the imaging device.
The position calculating device estimates a motion of the moving
object based on the image data and calculates a position of the
moving object in the interior of the elevator shaft based on the
distance data. The memory device stores the distance data and the
image data.
[0028] According to another embodiment, an elevator shaft inner
dimension measurement controller includes a calculator, a position
calculating device and a memory device. The calculator performs an
operation on distance data and image data. The distance data is
obtained from a distance measuring instrument including a laser
rangefinder mounted to a moving object moving through an interior
of an elevator shaft. The laser rangefinder irradiates laser light
on an inner wall of the elevator shaft. The image data is obtained
from an imaging device including a first camera mounted to the
moving object. The first camera images the interior of the elevator
shaft. The position calculating device estimates a motion of the
moving object based on the image data and calculates a position of
the moving object in the interior of the elevator shaft based on
the distance data. The memory device stores the distance data and
the image data.
[0029] According to another embodiment, an elevator shaft inner
dimension measurement method includes performing an operation on
distance data and image data. The distance data is obtained from a
distance measuring instrument including a laser rangefinder mounted
to a moving object moving through an interior of an elevator shaft.
The laser rangefinder irradiates laser light on an inner wall of
the elevator shaft. The image data is obtained from an imaging
device including a first camera mounted to the moving object. The
first camera images the interior of the elevator shaft. The method
includes estimating a motion of the moving object based on the
image data and calculating a position of the moving object in the
interior of the elevator shaft based on the distance data. The
method includes storing the distance data and the image data.
[0030] Various embodiments will be described hereinafter with
reference to the accompanying drawings.
[0031] The drawings are schematic or conceptual; and the
relationships between the thicknesses and widths of portions, the
proportions of sizes between portions, etc., are not necessarily
the same as the actual values thereof. Further, the dimensions
and/or the proportions may be illustrated differently between the
drawings, even in the case where the same portion is
illustrated.
[0032] In the drawings and the specification of the application,
components similar to those described in regard to a drawing
thereinabove are marked with like reference numerals, and a
detailed description is omitted as appropriate.
[0033] FIG. 1 is a block diagram showing an elevator shaft inner
dimension measuring device according to an embodiment. FIG. 2 is a
flowchart describing the elevator shaft inner dimension measurement
method according to the embodiment.
[0034] FIG. 3 is a schematic plan view showing the elevator shaft
inner dimension measuring device according to the embodiment.
[0035] The block diagram shown in FIG. 1 is an example of the
relevant components of the elevator shaft inner dimension measuring
device according to the embodiment and does not necessarily match
the configuration of the actual program module.
[0036] The elevator shaft inner dimension measuring device 100
includes an imaging device 110, a distance measuring instrument
120, and a controller (an elevator shaft inner dimension
measurement controller) 130. The controller 130 corresponds to the
elevator shaft inner dimension measurement controller according to
the embodiment. The controller 130 includes a calculator 131, a
memory device 133, and a position calculating device 135.
[0037] The controller 130 may be an external device that is
different from the elevator shaft inner dimension measuring device
100 or may be a device included in the elevator shaft inner
dimension measuring device 100. The hardware configuration shown in
FIG. 1 is an example; and a portion of the controller 130 or the
entire controller 130 according to the embodiments and the specific
examples may be realized as an integrated circuit such as LSI
(Large Scale Integration), etc., or an IC (Integrated Circuit)
chipset. Each functional block may be provided with processing
features individually; or some or all of the functional blocks may
be provided with a processing feature by being integrated. The
integrated circuit is not limited to LSI and may be realized using
a dedicated circuit or a general-purpose processor.
[0038] A moving apparatus 140 is provided in at least one of the
interior of an elevator shaft 210 or outside the elevator shaft
210. The moving apparatus 140 moves a moving object in the interior
of the elevator shaft 210 in two directions (e.g., vertical
directions or perpendicular directions). The moving object is, for
example, an elevator car 220. Or, the moving object is, for
example, a counterweight 230. However, the moving object is not
limited to the elevator car 220 or the counterweight 230. In the
example shown in FIG. 3, the elevator shaft inner dimension
measuring device 100 is mounted to an upper portion 221 of the
elevator car 220.
[0039] The imaging device 110 includes a first camera 111 and
images an inner wall 211 of the elevator shaft 210. A digital
camera that can receive visible light, a digital camera that can
receive infrared light, etc., are examples of the first camera
111.
[0040] The distance measuring instrument 120 includes a first laser
rangefinder 121 and irradiates laser light toward the inner wall
211 of the elevator shaft 210 inside a first field of view (an
imaging range) 115 of the imaging device 110. A time-difference
laser rangefinder, a phase-difference laser rangefinder, etc., are
examples of the first laser rangefinder 121. The time-difference
laser rangefinder calculates the distance between the laser
rangefinder and a measurement object by measuring the time from
when the laser light is irradiated to when the laser light is
reflected by the measurement object and returns to the laser
rangefinder. The phase-difference laser rangefinder determines the
distance between the laser rangefinder and the measurement object
by irradiating laser light modulated into a plurality and by
performing the determination based on the phase difference of the
diffuse reflection component of the laser light that strikes the
measurement object and returns to the laser rangefinder. Or, laser
rangefinders can be classified based on the angle in which the
laser light can be irradiated. A horizontal laser and a
two-dimensional laser are examples of the first laser rangefinder
121. The horizontal laser can irradiate laser light in a complete
circle of 360 degrees in the horizontal direction. In other words,
the horizontal laser can irradiate the laser light in a complete
circle of 360 degrees around an axis of the movement direction of
the moving object. The two-dimensional laser can irradiate the
laser light horizontally and perpendicularly in a constant
irradiation range.
[0041] The calculator 131 performs operations on the data acquired
from the imaging device 110 and the data acquired from the distance
measuring instrument 120. The calculator 131 also controls the
imaging device 110 and the distance measuring instrument 120.
[0042] The memory device 133 stores the data acquired from the
imaging device 110 and the data acquired from the distance
measuring instrument 120.
[0043] The position calculating device 135 calculates the position
of the moving object (the example of FIG. 3, the elevator car 220)
in the interior of the elevator shaft 210 based on the image data
obtained from the imaging device 110 and the distance data obtained
from the distance measuring instrument 120.
[0044] The moving apparatus 140 moves the elevator car 220 in the
interior of the elevator shaft 210.
[0045] The processing of the elevator shaft inner dimension
measuring device 100 according to the embodiment will now be
described. Here, an example will be described in which the moving
object is the elevator car 220 as shown in FIG. 3.
[0046] As shown in FIG. 2, the imaging device 110 images the range
(the first field of view 115) in the travel direction of the
elevator car 220 (step S111).
[0047] More specifically, the imaging device 110 images the
interior of the elevator shaft 210 to acquire an image (step S111).
The imaging device 110 is mounted to the elevator car 220 inside
the elevator shaft 210.
[0048] The calibration of calculating the focal length of the first
camera 111, etc., the calibration of calculating the positional
relationship (the rotation and the translation) between the imaging
device 110 and the distance measuring instrument 120, etc., are
performed beforehand. For example, the calibration method between
the imaging device 110 and the distance measuring instrument 120 is
as described in the reference document "Reliable Automatic
Camera-Laser Calibration (Australasian Conference on Robotics and
Automation 2010)," etc.
[0049] As shown in FIG. 3, in the case where the elevator shaft
inner dimension measuring device 100 is mounted to the upper
portion 221 of the elevator car 220, the imaging device 110 images
the upper range of the elevator shaft 210 from the upper portion
221 of the elevator car 220 in the direction toward a ceiling 213
of the elevator shaft 210.
[0050] Modifications of the mounting method of the elevator shaft
inner dimension measuring device will now be described.
[0051] FIG. 4 is a schematic plan view showing a modification of
the mounting method of the elevator shaft inner dimension measuring
device.
[0052] FIG. 5 is a schematic plan view showing another modification
of the mounting method of the elevator shaft inner dimension
measuring device.
[0053] FIG. 6 is a schematic plan view showing another modification
of the mounting method of the elevator shaft inner dimension
measuring device.
[0054] In the example shown in FIG. 4, the elevator shaft inner
dimension measuring device 100 is mounted to a lower portion 223 of
the elevator car 220. In such a case, the imaging device 110 images
the lower range of the elevator shaft 210 from the lower portion
223 of the elevator car 220 in the direction toward the pit (the
floor) of the elevator shaft 210.
[0055] In the example shown in FIG. 5, the elevator shaft inner
dimension measuring device 100 is mounted to an upper portion 231
of the counterweight 230. In such a case, the imaging device 110
images the upper range of the elevator shaft 210 from the upper
portion 231 of the counterweight 230 in the direction toward the
ceiling 213 of the elevator shaft 210.
[0056] In the example shown in FIG. 6, the elevator shaft inner
dimension measuring device 100 is mounted to a lower portion 233 of
the counterweight 230. In such a case, the imaging device 110
images the lower range of the elevator shaft 210 from the lower
portion 233 of the counterweight 230 in the direction toward the
pit (the floor) of the elevator shaft 210.
[0057] Returning now to FIG. 1 to FIG. 3, the camera included in
the imaging device 110 may range from those having constant angles
of view to omni-directional cameras that can perform
omni-directional imaging in 360 degrees. An omni-directional camera
can image the inner wall 211 of the elevator shaft 210 in all
directions in 360 degrees around the movement direction of the
moving object as an axis. It is desirable for the imaging device
110 to image in the travel direction of the elevator car 220 on
which the elevator shaft inner dimension measuring device 100 is
mounted. However, it is unnecessary to mount the imaging device 110
to be parallel or perpendicular to the axis of the travel direction
of the elevator car 220.
[0058] The distance measuring instrument 120 acquires the distance
values by measuring the reflected light of the laser light
irradiated from the distance measuring instrument 120
(specifically, the first laser rangefinder 121) mounted to the
elevator car 220 inside the elevator shaft 210 (step S112).
[0059] The first laser rangefinder 121 that is included in the
distance measuring instrument 120 scans the laser light irradiated
in a relatively narrow range and acquires the distance values
between the first laser rangefinder 121 and each position. That is,
the first laser rangefinder 121 irradiates the laser light over a
prescribed region as in an irradiation region 121a shown in FIG.
3.
[0060] The distance measuring instrument 120 irradiates the laser
light at an irradiation angle to shorten the distance (the
measurement distance) between the inner wall 211 of the elevator
shaft 210 and a projection region 121b of the irradiation region
121a of the laser light projected onto the image that is imaged by
the imaging device 110 (referring to FIG. 7A to FIG. 7C) and
shorten the distance (pixel units) between the projection region
121b and a center position 119 of the image of the imaging device
110 (the optical center position of the lens, referring to FIG. 7A
to FIG. 7C).
[0061] This will now be described further with reference to FIG. 7A
to FIG. 7C.
[0062] FIG. 7A to FIG. 7C are schematic plan views showing examples
of the projection region of the irradiation region of the laser
light projected onto the image that is imaged.
[0063] That is, FIG. 7A to FIG. 7C show examples of the projection
region 121b of the irradiation region 121a of the laser light
projected onto the image of the interior of the elevator shaft
210.
[0064] For example, the examples of the projection onto the image
of the projection region 121b of the irradiation region 121a of the
laser light irradiated from the first laser rangefinder 121 are as
shown in FIG. 7A to FIG. 7C. The irradiation region 121a of the
laser light corresponding to the projection region 121b shown in
FIG. 7A is different from the irradiation region 121a of the laser
light corresponding to the projection region 121b shown in FIG. 7B
and FIG. 7C. The irradiation region 121a of the laser light
corresponding to the projection region 121b shown in FIG. 7B is
different from the irradiation region 121a of the laser light
corresponding to the projection region 121b shown in FIG. 7C.
[0065] The projection region 121b of the irradiation region 121a of
the laser light projected onto the image of the interior of the
elevator shaft 210 is more proximal to the center position 119 of
the image for the example shown in FIG. 7A than for the example
shown in FIG. 7C. The distance (the measurement distance) between
the projection region 121b and the inner wall 211 of the elevator
shaft 210 is shorter for the example shown in FIG. 7A than for the
example shown in FIG. 7B.
[0066] The projection region 121b of the irradiation region 121a of
the laser light projected onto the image of the interior of the
elevator shaft 210 is more proximal to the center position 119 of
the image for the example shown in FIG. 7B than for the examples
shown in FIG. 7A and FIG. 7C. The distance (the measurement
distance) between the projection region 121b and the inner wall 211
of the elevator shaft 210 is longer for the example shown in FIG.
7B than for the examples shown in FIG. 7A and FIG. 7C. That is, the
measurement distance is longer for the example shown in FIG. 7B
than for the examples shown in FIG. 7A and FIG. 7C because the
projection region 121b passes through the ceiling 213 in the image
that is imaged.
[0067] The projection region 121b of the irradiation region 121a of
the laser light projected onto the image of the interior of the
elevator shaft 210 is more distal to the center position 119 of the
image for the example shown in FIG. 7C than for the examples shown
in FIG. 7A and FIG. 7B. The distance (the measurement distance)
between the projection region 121b and the inner wall 211 of the
elevator shaft 210 is shorter for the example shown in FIG. 7C than
for the example shown in FIG. 7B.
[0068] One reason that it is better for the projection region 121b
of the irradiation region 121a of the laser light projected onto
the image of the interior of the elevator shaft 210 to be more
proximal to the center position 119 of the image is that, for
example, the distortion of the image occurring due to the
characteristics of the lens of the imaging device 110 is relatively
small at positions relatively proximal to the center position 119
of the image. Thereby, the precision of the position of the
elevator car 220 in the interior of the elevator shaft 210
calculated in step S113 shown in FIG. 2 becomes high.
[0069] One reason that it is better for the distance (the
measurement distance) between the inner wall 211 of the elevator
shaft 210 and the projection region 121b of the irradiation region
121a of the laser light projected onto the image of the interior of
the elevator shaft 210 to be small is that, for example, the
measured intensity of the laser light is relatively high and the
reliability is relatively high at positions where the measurement
distance of the projection region 121b is relatively short.
Thereby, the precision of the position of the elevator car 220 of
the interior of the elevator shaft 210 calculated in step S113
shown in FIG. 2 becomes high.
[0070] Returning now to FIG. 2, the position calculating device 135
calculates the position of the elevator car 220 inside the elevator
shaft 210 by estimating the motion (the rotation and the
translation) of the elevator car 220 based on the image data
obtained from the imaging device 110 and by acquiring the true
scale based on the distance data obtained from the distance
measuring instrument 120 (step S113).
[0071] The processing of calculating the position of the elevator
car 220 inside the elevator shaft 210 based on the image data
imaged in step S111 includes first and second processing.
[0072] The first processing is executed when two images that are
imaged at mutually-different positions are first input to the
position calculating device 135 at the start of the processing of
calculating the position of the elevator car 220. In the first
processing, first, the position calculating device 135 detects
feature points between the two images that are imaged at the
mutually-different positions and performs a search for the
corresponding positions. "Feature point" refers to a characteristic
portion inside the image that is imaged by the imaging device 110.
If the correspondence of the feature points between the two images
can be known, the positions (the translation vectors) of the first
camera 111 for when the two images were imaged and the orientations
(the rotation matrixes) of the first camera 111 for when the two
images were imaged can be determined.
[0073] The position of the first camera 111 when the first image is
imaged is different from the position of the first camera 111 when
the second image is imaged. The orientation of the first camera 111
when the first image is imaged is different from the orientation of
the first camera 111 when the second image is imaged.
[0074] Continuing, the position calculating device 135 calculates
the three-dimensional positions of the feature points by the
principle of triangulation based on the correspondence of the
feature points, the calculated positions of the first camera 111,
and the calculated orientations of the first camera 111.
[0075] The second processing is executed when an image that is
imaged at a position different from the positions of the two images
of the first processing is input to the position calculating device
135 in the state in which the three-dimensional positions of the
feature points are known. At this time, the position calculating
device 135 estimates the motion of the elevator car 220 based on
the positions of the feature points in the image and the
three-dimensional positions of the feature points. The position
calculating device 135 can estimate the position of the elevator
car 220 inside the elevator shaft 210 at each time by repeatedly
performing the second processing.
[0076] The first processing and the second processing will now be
described further.
[0077] FIG. 8A and FIG. 8B are schematic views showing examples of
motion estimation charts of the first camera.
[0078] FIG. 9A and FIG. 9B are schematic views showing another
example of motion estimation charts of the first camera.
[0079] FIG. 10 is a schematic view showing an example of a scale
estimation chart of the first laser rangefinder.
[0080] In the first processing, the three-dimensional positions of
the feature points, the information of the position of the first
camera 111, and the information of the orientation of the first
camera 111 are unknown. Therefore, first, the position calculating
device 135 performs processing to determine the position of the
first camera 111 and the orientation of the first camera 111 based
on the two images imaged from mutually-different positions. The
position calculating device 135 extracts the feature points based
on the two images that are the input. It is desirable to suppress
the concentration of the feature points in a portion of the image;
and it is desirable for the feature points not to be detected
within a constant area around the feature points.
[0081] Continuing as shown in FIG. 9B, the position calculating
device 135 performs a search for the corresponding positions of the
feature points between the two images (a first image 117a and a
second image 117b). The search for the corresponding positions is
performed by setting a relatively small region around the feature
points and by evaluating the degree of similarity using SSD (Sum of
Squared Difference), etc., based on the luminance pattern of the
images. If the correspondence of the feature points between the two
images can be known, the positions (the translation vectors) of the
first camera 111 for when the two images were imaged and the
orientations (the rotation matrixes) of the first camera 111 for
when the two images were imaged can be determined.
[0082] A first image position 241a is the position on the first
image 117a of a first feature point 241. A second image position
242a is the position on the first image 117a of a second feature
point 242. A third image position 243a is the position on the first
image 117a of a third feature point 243.
[0083] A first image position 241b is the position associated with
the first image position 241a as a result of the search for the
corresponding positions described above. That is, the first image
position 241b is the position on the second image 117b of the first
feature point 241. A second image position 242b is the position
associated with the second image position 242a as a result of the
search for the corresponding positions described above. That is,
the second image position 242b is the position on the second image
117b of the second feature point 242. A third image position 243b
is the position associated with the third image position 243a as a
result of the search for the corresponding positions described
above. That is, the third image position 243b is the position on
the second image 117b of the third feature point 243.
[0084] The position of the first camera 111 when the first image
(the first image 117a) is imaged is different from the position of
the first camera 111 when the second image (the second image 117b)
is imaged. The orientation of the first camera 111 when the first
image is imaged is different from the orientation of the first
camera 111 when the second image is imaged.
[0085] The position calculating device 135 determines the
three-dimensional positions of the feature points based on the
positional relationship of the feature points in the image and the
calculated spatial positional relationship of the first camera 111.
The initial image (the first image 117a) of the first processing
matches the global coordinates at the position of the first camera
111. The rotation matrix is taken to be the identity matrix; and
the translation vector is taken to be the zero vector.
[0086] The second processing estimates the position of the first
camera 111 (the moving object inside the elevator shaft 210) and
the orientation of the first camera 111 (the moving object inside
the elevator shaft 210) in the state in which the three-dimensional
positions of the feature points are determined by the first
processing. As shown in FIG. 9B, first, the position calculating
device 135 finds feature points in the input image that match the
feature points detected by the first processing and forms
associations (feature point tracking). In the case where the first
camera 111 has not moved greatly from the previous time, the
position calculating device 135 may perform the feature point
tracking by searching around the feature points found in the image
of the previous time.
[0087] In the example shown in FIG. 8B, a first image position 241c
is the position associated with the first image position 241b as a
result of the feature point tracking described above. That is, the
first image position 241c is the position on a third image 117c of
the first feature point 241. A second image position 242c is the
position associated with the second image position 242b as a result
of the feature point tracking described above. That is, the second
image position 242c is the position on the third image 117c of the
second feature point 242. A third image position 243c is the
position associated with the third image position 243b as a result
of the feature point tracking described above. That is, the third
image position 243c is the position on the third image 117c of the
third feature point 243.
[0088] In the example shown in FIG. 8B, a first projection position
241c' is the position of the three-dimensional position of the
first feature point 241 projected onto the first camera 111 using
the position of the first camera 111 and the orientation of the
first camera 111 ("'" indicates a projected point). That is, the
first projection position 241c' is the position on the third image
117c of the first feature point 241. A second projection position
242c' is the position of the three-dimensional position of the
second feature point 242 projected onto the first camera 111 using
the position of the first camera 111 and the orientation of the
first camera 111. That is, the second projection position 242c' is
the position on the third image 117c of the second feature point
242. A third projection position 243c' is the position of the
three-dimensional position of the third feature point 243 projected
onto the first camera 111 using the position of the first camera
111 and the orientation of the first camera 111. That is, the third
projection position 243c' is the position on the third image 117c
of the third feature point 243.
[0089] The position calculating device 135 estimates the position
of the first camera 111 and the orientation of the first camera 111
based on the three-dimensional positions of the tracked feature
points and the coordinates (the positions) in the image of the
feature points. FIG. 8A and FIG. 8B are intuitive illustrations of
the processing executed by the position calculating device 135.
FIG. 8A and FIG. 8B show the state when the three-dimensional
positions are kept the same for the first feature point 241, the
second feature point 242, and the third feature point 243, and the
position of the first camera 111 and the orientation of the first
camera 111 are changed.
[0090] In FIG. 8A, the position of the first camera 111 and the
orientation of the first camera 111 are correct. FIG. 8A shows that
the positions in the image of the feature points that are found
match the three-dimensional positions of the feature points
projected onto the first camera 111.
[0091] In the example shown in FIG. 8A, a first projection position
241b' is the three-dimensional position of the first feature point
241 projected onto the first camera 111 using the position of the
first camera 111 and the orientation of the first camera 111. That
is, the first projection position 241b' is the position on the
second image 117b of the first feature point 241. A second
projection position 242b' is the three-dimensional position of the
second feature point 242 projected onto the first camera 111 using
the position of the first camera 111 and the orientation of the
first camera 111. That is, the second projection position 242b' is
the position on the second image 117b of the second feature point
242. A third projection position 243b' is the three-dimensional
position of the third feature point 243 projected onto the first
camera 111 using the position of the first camera 111 and the
orientation of the first camera 111. That is, the third projection
position 243b' is the position on the second image 117b of the
third feature point 243.
[0092] In the example shown in FIG. 8B, it can be seen that an
error occurs in the projection positions. The position calculating
device 135 projects, onto the image based on a rotation matrix R of
the first camera 111 and a translation vector t of the first camera
111, the three-dimensional positions of the feature points and the
positions in the image of the feature points that are found. The
position calculating device 135 estimates the rotation matrix R and
the translation vector t so that the difference between the
three-dimensional positions of the feature points and the positions
in the image of the feature points that are found becomes small.
The processing is expressed by the following formula.
E ( R ^ , t ^ ) = min R , t i ( x i - P ( R , t ) X i ) 2 Formula (
1 ) ##EQU00001##
x.sub.i: position in image of ith feature that was found P(R, t):
perspective projection matrix R: rotation matrix of first camera
111 t: translation vector of first camera 111 X.sub.i:
three-dimensional position of feature expressed in homogeneous
coordinates
[0093] The rotation matrix R and the translation vector t are
determined by performing nonlinear optimization to minimize the
cost function of Formula (1). Because the movement between adjacent
images is not very large, the motion estimation result that is
estimated at the previous time can be utilized as the initial
value.
[0094] However, the scale is indefinite for the translation vector
t that is determined. The distance data that is obtained in step
S112 is used to cause the scale of the translation vector t to
match the actual scale (the true scale).
[0095] In the processing of transforming to true scale, first, the
projection region 121b of the laser light is tracked in the image.
Then, the ratio of the true scale and the camera scale is
calculated based on the tracked laser light. Thereby, the scale of
the calculated translation vector t is transformed to true scale.
As shown in FIG. 10, the tracking of the laser light is the
tracking of the points or region of the laser light in the image
between images that are imaged at different times. Specifically,
for a pixel xt of the image of the first camera 111 where a laser
point Xt irradiated at time t is projected, a pixel x't+1 where the
laser point Xt is projected in the image of the first camera 111 at
time t+1 is calculated ("'" indicates a tracked point). The
three-dimensional position of the tracked pixel x't+1 can be
calculated using the principle of triangulation based on the
calculated position (the translation vector t) of the first camera
111 and the calculated orientation (the rotation matrix R) of the
first camera 111. Thereby, the scale of the translation vector t
can be transformed to true scale by comparing the ratio of the
calculated three-dimensional position and the laser point Xt.
[0096] Returning now to FIG. 2, the memory device 133 stores the
image data obtained in step S111 (step S114). The memory device 133
stores the three-dimensional configuration obtained by transforming
the distance data obtained in step S112 into global coordinates
(step S114). The transformation of the distance data into global
coordinates is performed based on the position of the elevator car
220 and the orientation of the elevator car 220 obtained for each
time by the calculation in step S113.
[0097] Continuing, the controller 130 determines whether or not to
end the processing (step S115). In the case where the controller
130 determines not to end the processing (step S115: No), the
processing described above in regard to step S111 to step S114 is
executed repeatedly. In the case where the controller 130
determines to end the processing (step S115: Yes), the processing
of the elevator shaft inner dimension measuring device 100
ends.
[0098] The case where the distance measuring instrument 120
includes the first laser rangefinder 121 is described in the
embodiment. However, the number of laser rangefinders included in
the distance measuring instrument 120 is not limited thereto. The
distance measuring instrument 120 may include two or more laser
rangefinders.
[0099] This will now be described further with reference to the
drawings.
[0100] FIG. 11 is a schematic plan view showing an elevator shaft
inner dimension measuring device according to another
embodiment.
[0101] The distance measuring instrument 120 of the elevator shaft
inner dimension measuring device 100a shown in FIG. 11 includes the
first laser rangefinder 121 and a second laser rangefinder 122. The
first laser rangefinder 121 and the second laser rangefinder 122
are mounted to the upper portion 221 of the elevator car 220. The
first laser rangefinder 121 irradiates laser light on the
irradiation region 121a. The second laser rangefinder 122
irradiates laser light on an irradiation region 122a.
[0102] The imaging device 110 is provided between the first laser
rangefinder 121 and the second laser rangefinder 122. The moving
object to which the elevator shaft inner dimension measuring device
100a is mounted is, for example, the elevator car 220. Or, the
moving object to which the elevator shaft inner dimension measuring
device 100a is mounted is, for example, the counterweight 230.
[0103] It is desirable for the elevator shaft inner dimension
measuring device 100a to be mounted to the upper portion 221 of the
elevator car 220 or the lower portion 223 of the elevator car 220.
It is desirable for the elevator shaft inner dimension measuring
device 100a to be mounted to the upper portion 231 of the
counterweight 230 or the lower portion 233 of the counterweight
230.
[0104] According to the embodiment, the elevator shaft inner
dimension measuring devices 100 and 100a measure the position,
orientation, and motion of the elevator car 220 or the elevator
shaft inner dimension measuring devices 100 and 100a based on the
data obtained by the distance measuring instrument 120 and the
imaging device 110 imaging the inner wall 211 of the elevator shaft
210. The imaging device 110 and the distance measuring instrument
120 are mounted to the elevator car 220. Thereby, it is unnecessary
for the elevator shaft inner dimension measuring devices 100 and
100a to measure the distance between the ceiling 213 and the
elevator shaft inner dimension measuring devices 100 and 100a.
Moreover, it is unnecessary to mount a roller or a rotary encoder
on the guiderail of the elevator. Therefore, the effort to mount
the devices is eliminated; and, for example, it is possible to
measure the dimensions of the interior of the elevator shaft 210
even in the case where the imaging environment such as the size of
the guiderail or the like is different. Thereby, the dimensions of
the interior of the elevator shaft 210 can be measured relatively
easily or in a relatively short period of time.
[0105] FIG. 12 is a block diagram showing an elevator shaft inner
dimension measuring device according to a modification of the
embodiment.
[0106] FIG. 13A and FIG. 13B are schematic plan views showing
rotation states of the laser rangefinder.
[0107] FIG. 14A and FIG. 14B are schematic plan views showing other
rotation states of the laser rangefinder.
[0108] FIG. 13A and FIG. 14A are schematic plan views showing the
position of the laser rangefinder in the outward path of the
vertical motion of the elevator car 220. FIG. 13B and FIG. 14B are
schematic plan views showing the position of the laser rangefinder
in the inward path of the vertical motion of the elevator car
220.
[0109] The block diagram shown in FIG. 12 is an example of the
relevant components of the elevator shaft inner dimension measuring
device according to the embodiment and does not necessarily match
the configuration of the actual program module.
[0110] In the embodiment described above in regard to FIG. 1, in
the case where the distance measuring instrument 120 includes one
laser rangefinder (first laser rangefinder 121), the first laser
rangefinder 121 cannot measure the elevator shaft 210 in 360
degrees unless the first laser rangefinder 121 has an irradiation
angle of 360 degrees. Therefore, compared to the elevator shaft
inner dimension measuring device 100 shown in FIG. 1, the elevator
shaft inner dimension measuring device 100b shown in FIG. 12
further includes a rotating device 150. The rotating device 150
holds the first laser rangefinder 121.
[0111] The elevator shaft inner dimension measuring device 100b
modifies the irradiation position of the first laser rangefinder
121 between the outward path of the vertical motion of the elevator
car 220 and the inward path of the vertical motion of the elevator
car 220 by using the rotating device 150. The first laser
rangefinder 121 can measure the interior of the elevator shaft 210
in 360 degrees as the elevator car 220 makes one round trip through
the elevator shaft 210. To integrate the measurement data of the
first laser rangefinder 121 of the outward path of the vertical
motion of the elevator car 220 and the measurement data of the
first laser rangefinder 121 of the inward path of the vertical
motion of the elevator car 220, the elevator shaft inner dimension
measuring device 100b modifies the irradiation angle of the first
laser rangefinder 121 using the rotating device 150 while the
position of the imaging device 110 is fixed.
[0112] In the example shown in FIG. 13A and FIG. 13B, the position
of the first laser rangefinder 121 of the outward path is different
from the position of the first laser rangefinder 121 of the inward
path due to the rotating device 150.
[0113] In the example shown in FIG. 14A and FIG. 14B, the position
of the first laser rangefinder 121 of the outward path is the same
as the position of the first laser rangefinder 121 of the inward
path. The angle of the first laser rangefinder 121 of the outward
path is different from the angle of the first laser rangefinder 121
of the inward path due to the rotating device 150. That is, in the
example shown in FIG. 14A and FIG. 14B, the first laser rangefinder
121 rotates the first laser rangefinder 121 around the optical
axis.
[0114] In the examples shown in FIG. 13A, FIG. 13B, FIG. 14A, and
FIG. 14B, the elevator shaft inner dimension measuring device 100b
can modify the irradiation angle of the first laser rangefinder 121
while the position of the imaging device 110 is fixed, that is,
while the global coordinate system is fixed. Therefore, the
elevator shaft inner dimension measuring device 100b can easily
integrate the measurement data of the first laser rangefinder 121
of the outward path and the measurement data of the first laser
rangefinder 121 of the inward path.
[0115] The global coordinate system moves in the case where the
position of the imaging device 110 is rotated by the rotating
device 150. Therefore, it is possible to integrate the measurement
data of the first laser rangefinder 121 by determining information
relating to the rotation angle of the rotating device 150 or the
correspondence between the coordinate system prior to the rotation
and the coordinate system after the rotation.
[0116] FIG. 15 is a block diagram showing an elevator shaft inner
dimension measuring device according to one other embodiment.
[0117] FIG. 16 is a flowchart describing an elevator shaft inner
dimension measurement method according to the one other
embodiment.
[0118] FIG. 17 is a schematic plan view showing the elevator shaft
inner dimension measuring device according to the one other
embodiment.
[0119] The block diagram shown in FIG. 15 is an example of the
relevant components of the elevator shaft inner dimension measuring
device according to the embodiment and does not necessarily match
the configuration of the actual program module.
[0120] The elevator shaft inner dimension measuring device 100c
according to the embodiment shown in FIG. 15 estimates the motion
(the rotation and the translation) of the moving object based on
the image data imaged by stereo cameras of the imaging device. The
elevator shaft inner dimension measuring device 100c calculates the
position of the moving object inside the elevator shaft 210 by
acquiring the true scale based on the image data imaged by the
stereo cameras of the imaging device.
[0121] As shown in FIG. 17, the imaging device 110 includes the
first camera 111 and a second camera 112. The first camera 111 and
the second camera 112 are mounted to the upper portion 221 of the
elevator car 220. The distance measuring instrument 120 is provided
between the first camera 111 and the second camera 112. The moving
object to which the elevator shaft inner dimension measuring device
100c is mounted is, for example, the elevator car 220. Or, the
moving object to which the elevator shaft inner dimension measuring
device 100c is mounted is, for example, the counterweight 230.
[0122] It is desirable for the elevator shaft inner dimension
measuring device 100c to be mounted to the upper portion 221 of the
elevator car 220 or the lower portion 223 of the elevator car 220.
It is desirable for the elevator shaft inner dimension measuring
device 100c to be mounted to the upper portion 231 of the
counterweight 230 or the lower portion 233 of the counterweight
230.
[0123] Here, an example will be described in which the elevator
shaft inner dimension measuring device 100c is mounted to the upper
portion 221 of the elevator car 220 as shown in FIG. 17. In other
words, an example will be described in which the moving object is
the elevator car 220.
[0124] As shown in FIG. 16, the imaging device 110 images the range
(the first field of view 115) in the travel direction of the
elevator car 220 (step S211).
[0125] More specifically, the imaging device 110 acquires an image
by imaging the interior of the elevator shaft 210 (step S211).
[0126] As shown in FIG. 17, the first camera 111 images the first
field of view 115. The second camera 112 images a second field of
view 116. The first camera 111 is as described above in regard to
FIG. 1 to FIG. 3. A digital camera that can receive visible light,
a digital camera that can receive infrared light, etc., are
examples of the second camera 112. The second field of view 116 and
at least a portion of the first field of view 115 overlap.
[0127] The calibration of calculating the focal length of the first
camera 111, the focal length of the second camera 112, etc., the
calibration of calculating the positional relationship (the
rotation and the translation) between the first camera 111 and the
second camera 112, the calibration of calculating the positional
relationship (the rotation and the translation) between the imaging
device 110 and the distance measuring instrument 120, etc., are
performed beforehand. The calibration method between the first
camera 111 and the second camera 112 is, for example, as described
in the reference document "Flexible camera calibration by viewing a
plane from unknown orientation (IEEE Int. Conf. Computer Vision
1999)," etc.
[0128] As shown in FIG. 17, in the case where the elevator shaft
inner dimension measuring device 100c is mounted to the upper
portion 221 of the elevator car 220, the imaging device 110 images
the upper range of the elevator shaft 210 from the upper portion
221 of the elevator car 220 in the direction toward the ceiling 213
of the elevator shaft 210.
[0129] The case where the elevator shaft inner dimension measuring
device 100c is mounted to the lower portion 223 of the elevator car
220 is as described above in regard to FIG. 4. The case where the
elevator shaft inner dimension measuring device 100c is mounted to
the upper portion 231 of the counterweight 230 is as described
above in regard to FIG. 5. The case where the elevator shaft inner
dimension measuring device 100c is mounted to the lower portion 233
of the counterweight 230 is as described above in regard to FIG.
6.
[0130] Returning now to FIG. 15 to FIG. 17, it is desirable for the
imaging device 110 to image in the travel direction of the elevator
car 220 to which the elevator shaft inner dimension measuring
device 100c is mounted. However, it is unnecessary for the imaging
device 110 to be mounted parallel or perpendicular to the axis in
the travel direction of the elevator car 220.
[0131] The distance measuring instrument 120 acquires the distance
values by measuring the reflected light of the laser light
irradiated from the distance measuring instrument 120
(specifically, the first laser rangefinder 121) mounted to the
elevator car 220 inside the elevator shaft 210 (step S212).
[0132] The distance measuring instrument 120 irradiates the laser
light at an irradiation angle to shorten the distance (the
measurement distance) between the inner wall 211 of the elevator
shaft 210 and the projection region 121b of the irradiation region
121a of the laser light projected onto the image of the imaging
device 110 (referring to FIG. 7A to FIG. 7C) and to shorten the
distance (pixel units) between the projection region 121b and the
center position 119 of the image of the imaging device 110 (the
optical center position of the lens, referring to FIG. 7A to FIG.
7C). This is as described above in regard to FIG. 1 to FIG. 3 and
FIG. 7A to FIG. 7C.
[0133] The position calculating device 135 calculates the position
of the elevator car 220 inside the elevator shaft 210 by estimating
the motion (the rotation and the translation) of the elevator car
220 based on multiple image data obtained from the imaging device
110 and by acquiring the true scale (step S213). That is, in step
S213, the position calculating device 135 calculates the position
of the elevator car 220 inside the elevator shaft 210 by estimating
the motion (the rotation and the translation) of the elevator car
220 based on the image data imaged by the imaging device 110 in
step S211 and by acquiring the true scale based on the positional
relationship between the first camera 111 and the second camera 112
calibrated beforehand.
[0134] The processing of calculating the position of the elevator
car 220 inside the elevator shaft 210 based on the multiple image
data imaged in step S211 includes the first and second
processing.
[0135] The first processing is executed when the image that is
imaged by the first camera 111 and the image that is imaged by the
second camera 112 are first input to the position calculating
device 135 at the start of the processing of calculating the
position of the elevator car 220. In the first processing, first,
the position calculating device 135 detects the feature points
based on the image of the first camera 111 and the image of the
second camera 112 and performs a search for the corresponding
positions between the image of the first camera 111 and the image
of the second camera 112.
[0136] Continuing, the position calculating device 135 calculates
the three-dimensional positions of the feature points by the
principle of triangulation based on the correspondence of the
feature points and the positional relationship between the first
camera 111 and the second camera 112 calibrated beforehand.
[0137] The second processing is executed when the image that is
imaged by the first camera 111 and the image that is imaged by the
second camera 112 are input to the position calculating device 135
in the state in which the three-dimensional positions of the
feature points are known. At this time, the position calculating
device 135 estimates the motion of the elevator car 220 based on
the three-dimensional positions of the feature points and the
positions of the feature points in the image. The position of the
elevator car 220 inside the elevator shaft 210 at each time can be
estimated by repeatedly performing the second processing.
[0138] The first processing and the second processing will now be
described further.
[0139] In the first processing, the three-dimensional positions of
the feature points, the information of the position of the first
camera 111, the information of the orientation of the first camera
111, the information of the position of the second camera 112, and
the information of the orientation of the second camera 112 are
unknown. Therefore, first, the position calculating device 135
performs processing to determine the position of the first camera
111, the orientation of the first camera 111, the position of the
second camera 112, and the orientation of the second camera 112
based on the image that is imaged by the first camera 111 and the
image that is imaged by the second camera 112. The position
calculating device 135 extracts the feature points based on the
image of the first camera 111 that is input and the image of the
second camera 112 that is input. It is desirable to suppress the
concentration of the feature points in a portion of the image; and
it is desirable for the feature points not to be detected within a
constant area around the feature points.
[0140] Continuing, the position calculating device 135 performs a
search for the corresponding positions of the feature points
between the image of the first camera 111 and the image of the
second camera 112. The search for the corresponding positions is
performed by setting a relatively small region around the feature
points and by evaluating the degree of similarity using SSD (Sum of
Squared Difference), etc., based on the luminance pattern of the
images. For the first camera 111 and the second camera 112, the
relative position between the first camera 111 and the second
camera 112 and the relative orientation between the first camera
111 and the second camera 112 are calibrated beforehand.
[0141] Therefore, the position calculating device 135 determines
the three-dimensional positions of the feature points based on the
positional relationship of the feature points between the image of
the first camera 111 and the image of the second camera 112, the
spatial position of the first camera 111, and the spatial position
of the second camera 112. The initial image of the first processing
matches the global coordinates at the position of the first camera
111 and the position of the second camera 112. The rotation matrix
is taken to be the identity matrix; and the translation vector is
taken to be the zero vector.
[0142] The second processing estimates the position of the first
camera 111 (the moving object inside the elevator shaft 210), the
orientation of the first camera 111 (the moving object inside the
elevator shaft 210), the position of the second camera 112 (the
moving object inside the elevator shaft 210), and the orientation
of the second camera 112 (the moving object inside the elevator
shaft 210) in the state in which the three-dimensional positions of
the feature points are determined by the first processing. First,
the position calculating device 135 finds the feature points that
match the feature points detected by the first processing for the
image of the first camera 111 that is input and the image of the
second camera 112 that is input and forms associations (feature
point tracking). In the case where the first camera 111 and the
second camera 112 have not moved greatly from the previous time,
the position calculating device 135 may perform the feature point
tracking by searching around the feature points found in the image
of the previous time.
[0143] The position calculating device 135 estimates the position
of the first camera 111, the orientation of the first camera 111,
the position of the second camera 112, and the orientation of the
second camera 112 based on the three-dimensional positions of the
tracked feature points and the coordinates (the positions) in the
image of the feature points. Here, for example, the same method as
the method described above in regard to FIG. 8A and FIG. 8B is
used.
[0144] The position calculating device 135 projects, onto the image
based on the rotation matrix R for the first camera 111 and the
second camera 112 and the translation vector t for the first camera
111 and the second camera 112, the three-dimensional positions of
the feature points and the positions in the image of the feature
points that are found. The position calculating device 135
estimates the rotation matrix R and the translation vector t so
that the difference between the three-dimensional positions of the
feature points and the positions in the image of the feature points
that are found becomes small. The processing is expressed by the
following formula.
E ( R ^ , t ^ ) = min R , t i ( x i - P ( R , t ) X i ) 2 Formula (
2 ) ##EQU00002##
x.sub.i: position in image of ith feature that was found P(R, t):
perspective projection matrix R: rotation matrix of first camera
111 and second camera 112 t: translation vector of first camera 111
and second camera 112 X.sub.i: three-dimensional position of
feature expressed in homogeneous coordinates
[0145] The rotation matrix R and the translation vector t are
determined by performing nonlinear optimization to minimize the
cost function of Formula (2). Because the movement between adjacent
images is not very large, the motion estimation result that is
estimated at the previous time can be utilized as the initial
value.
[0146] The scale of the translation vector t that is determined is
transformed to true scale based on the positional relationship
between the first camera 111 and the second camera 112 calibrated
beforehand. Therefore, as in the elevator shaft inner dimension
measuring devices 100, 100a, and 100b described above in regard to
FIG. 1 to FIG. 14B, it is unnecessary for the position calculating
device 135 to acquire the distance data from the distance measuring
instrument 120.
[0147] The processing of step S214 is the same as the processing of
step S114 described above in regard to FIG. 2. The processing of
step S215 is the same as the processing of step S115 described
above in regard to FIG. 2.
[0148] The case where the distance measuring instrument 120
includes the first laser rangefinder 121 is described in the
embodiment. However, the number of laser rangefinders included in
the distance measuring instrument 120 is not limited thereto. The
distance measuring instrument 120 may include two or more laser
rangefinders.
[0149] This will now be described further with reference to the
drawings.
[0150] FIG. 18 is a schematic plan view showing an elevator shaft
inner dimension measuring device according to another
embodiment.
[0151] The distance measuring instrument 120 of the elevator shaft
inner dimension measuring device 100d shown in FIG. 18 includes the
first laser rangefinder 121 and the second laser rangefinder 122.
The first laser rangefinder 121 and the second laser rangefinder
122 are mounted to the upper portion 221 of the elevator car 220.
The first laser rangefinder 121 irradiates laser light in the
irradiation region 121a toward the inside of the first field of
view 115 of the first camera 111. The second laser rangefinder 122
irradiates laser light in the irradiation region 122a toward the
inside of the second field of view 116 of the second camera
112.
[0152] The distance measuring instrument 120 is provided between
the first camera 111 and the second camera 112. The moving object
to which the elevator shaft inner dimension measuring device 100d
is mounted is, for example, the elevator car 220. Or, the moving
object to which the elevator shaft inner dimension measuring device
100d is mounted is, for example, the counterweight 230.
[0153] It is desirable for the elevator shaft inner dimension
measuring device 100d to be mounted to the upper portion 221 of the
elevator car 220 or the lower portion 223 of the elevator car 220.
It is desirable for the elevator shaft inner dimension measuring
device 100d to be mounted to the upper portion 231 of the
counterweight 230 or the lower portion 233 of the counterweight
230.
[0154] FIG. 19 is a block diagram showing an elevator shaft inner
dimension measuring device according to a modification of the
embodiment.
[0155] FIG. 20A and FIG. 20B are schematic plan views showing
rotation states of the laser rangefinder.
[0156] FIG. 21A and FIG. 21B are schematic plan views showing other
rotation states of the laser rangefinder.
[0157] FIG. 20A and FIG. 21A are schematic plan views showing the
position of the laser rangefinder in the outward path of the
vertical motion of the elevator car 220. FIG. 20B and FIG. 21B are
schematic plan views showing the position of the laser rangefinder
in the inward path of the vertical motion of the elevator car
220.
[0158] The block diagram shown in FIG. 19 is an example of the
relevant components of the elevator shaft inner dimension measuring
device according to the embodiment and does not necessarily match
the configuration of the actual program module.
[0159] In the embodiment described above in regard to FIG. 15, in
the case where the distance measuring instrument 120 includes one
laser rangefinder (the first laser rangefinder 121), the first
laser rangefinder 121 cannot measure the elevator shaft 210 in 360
degrees unless the first laser rangefinder 121 has an irradiation
angle of 360 degrees. Therefore, compared to the elevator shaft
inner dimension measuring device 100c shown in FIG. 15, the
elevator shaft inner dimension measuring device 100e shown in FIG.
19 further includes the rotating device 150.
[0160] The elevator shaft inner dimension measuring device 100e
modifies the irradiation position of the first laser rangefinder
121 between the outward path of the vertical motion of the elevator
car 220 and the inward path of the vertical motion of the elevator
car 220 by using the rotating device 150. The first laser
rangefinder 121 can measure the interior of the elevator shaft 210
in 360 degrees as the elevator car 220 makes one round trip through
the elevator shaft 210. To integrate the measurement data of the
first laser rangefinder 121 of the outward path of the vertical
motion of the elevator car 220 and the measurement data of the
first laser rangefinder 121 of the inward path of the vertical
motion of the elevator car 220, the elevator shaft inner dimension
measuring device 100e modifies the irradiation angle of the first
laser rangefinder 121 using the rotating device 150 while the
position of the imaging device 110 is fixed.
[0161] In the example shown in FIG. 20A and FIG. 20B, the position
of the first laser rangefinder 121 of the outward path is different
from the position of the first laser rangefinder 121 of the inward
path due to the rotating device 150.
[0162] The example shown in FIG. 21A and FIG. 21B, the position of
the first laser rangefinder 121 of the outward path is the same as
the position of the first laser rangefinder 121 of the inward path.
The angle of the first laser rangefinder 121 of the outward path is
different from the angle of the first laser rangefinder 121 of the
inward path due to the rotating device 150. That is, in the example
shown in FIG. 21A and FIG. 21B, the first laser rangefinder 121
rotates the first laser rangefinder 121 around the optical
axis.
[0163] In the examples shown in FIG. 20A, FIG. 20B, FIG. 21A, and
FIG. 21B, the elevator shaft inner dimension measuring device 100e
can modify the irradiation angle of the first laser rangefinder 121
while the position of the imaging device 110 is fixed, that is,
while the global coordinate system is fixed. Therefore, the
elevator shaft inner dimension measuring device 100e can easily
integrate the measurement data of the first laser rangefinder 121
of the outward path and the measurement data of the first laser
rangefinder 121 of the inward path.
[0164] The global coordinate system moves in the case where the
position of the imaging device 110 is rotated by the rotating
device 150. Therefore, it is possible to integrate the measurement
data of the first laser rangefinder 121 by determining information
relating to the rotation angle of the rotating device 150 or the
correspondence between the coordinate system prior to the rotation
and the coordinate system after the rotation.
[0165] According to the embodiments, the elevator shaft inner
dimension measuring devices 100c, 100d, and 100e measure the
position, orientation, and motion of the elevator car 220 or the
elevator shaft inner dimension measuring devices 100c, 100d, and
100e based on the data obtained by the distance measuring
instrument 120 and the imaging device 110 imaging the inner wall
211 of the elevator shaft 210. The imaging device 110 and the
distance measuring instrument 120 are mounted to the elevator car
220. Thereby, it is unnecessary for the elevator shaft inner
dimension measuring devices 100c, 100d, and 100e to measure the
distance between the ceiling 213 and the elevator shaft inner
dimension measuring devices 100c, 100d, and 100e. Moreover, it is
unnecessary to mount a roller or a rotary encoder on the guiderail
of the elevator. Therefore, the effort to mount the devices is
eliminated; and, for example, it is possible to measure the
dimensions of the interior of the elevator shaft 210 even in the
case where the imaging environment such as the size of the
guiderail or the like is different.
[0166] The imaging device 110 of the elevator shaft inner dimension
measuring devices 100c, 100d, and 100e includes the first camera
111 and the second camera 112. Therefore, the scale of the
translation vector t is transformed to true scale based on the
positional relationship between the first camera 111 and the second
camera 112 calibrated beforehand. Thereby, the position calculating
device 135 can calculate the position of the elevator car 220
inside the elevator shaft 210 without acquiring the distance data
from the distance measuring instrument 120 by acquiring the true
scale based on the positional relationship between the first camera
111 and the second camera 112 calibrated beforehand. Thereby, the
dimensions of the interior of the elevator shaft 210 can be
measured relatively easily or in a relatively short period of
time.
[0167] While certain embodiments have been described, these
embodiments have been presented by way of example only, and are not
intended to limit the scope of the inventions. Indeed, the novel
embodiments described herein may be embodied in a variety of other
forms; furthermore, various omissions, substitutions and changes in
the form of the embodiments described herein may be made without
departing from the spirit of the inventions. The accompanying
claims and their equivalents are intended to cover such forms or
modifications as would fall within the scope and spirit of the
invention.
* * * * *